I don’t know about others but for me, the male protagonist of any NTR genre should be the one to be hated the most.

Why would you hate the villain when it is their job to corrupt?
Why would you hate the girl when she is the one to be saved?

Why not hate the protagonist when it is supposed to be his fucking job to save the girl and win the day?
The answer is he is a fucking failure. So if you are sympathizing with the guy then you are a certified masochistic pussy.